Strand handling apparatus



March 2, 1943.

J. SELVIG STRAND HANDLI ZNG APPARATUS Filed June 12, 1940 INVENTOI? J. N. SELV/G' i me'waw- A TTOPIVF'V Patented Mar. 2, 1943 STRAND HANDLING APPARATUS John N. Selvig, Westfield, N. 1., assig'nor to Western Electric Company, Incorporated, New York, N. Y., a corporation of New York Application June 12, 1940, Serial No. 340,064

16 Claims.

This invention relates to strand handling apparatus, and more particularly to a device for compacting and polishing material in strand form.

There has been developed in recent years particularly for use in the communications arts and allied fields of electrical industry, a form of insulated electrical conductor in which a conductive wire is provided with a seamless sheath of felted pulp fibers, e. g., of wood or textile cellulosic material such as is used in making paper. In the manufacture of wire sheathed in this fashion, a ribbon of the wet felted fibers is first partially formed, the wire to be sheathed is laid thereon, and the forming of the ribbon completed, to pro duce a ribbon having the Wire embedded within and surrounded by the substance of the ribbon. It is then necessary to fold over the edges of the ribbon about the wire core and compact the folded mass together into what is substantially a seamless and wholly interfelted tube of the fibers about the core by forming, compacting and to some extent polishing the fibrous pulp of the ribbon.

An object of the present invention is to provide a simple, effective, reliable and durable device to form, compact and polish material in strand form drawn therethrough.

With the above and other objects in view, the

invention may be embodied in a device comprising as its essential element a relatively rigid rod-like member, formed into a helix enveloping a tubular surface through which to pass a strand, and in which the tubular inner envelope of the helix is first greater, then smaller and then finally greater again in diameter than the diameter of the strand emerging therefrom.

Other objects and features of the invention will appear from the following detailed description of one embodiment thereof taken in connection with the accompanying drawing, in which the single figure is a perspective view of a device constructed in accordance with the invention. 1

The invention as herein illustratively disclosed is embodied in a device for folding, compacting and polishing a ribbon of wet pulpous material, e. g., paper pulp, containing a wire embedded therein, into a substantially seamless, uniform, cylindrical, tubular sheath about the wire.

The formation of the ribbon with the wire embedded therein forms no part of the present invention and so is not described herein in detail. Reference may be had, if desired, to U. S. Patent No. 1,615,381, granted January 25, 1927, to W. F.

Hosford, for a suitable method and apparatus of making the ribbon around the wire.

The wire I, drawn from some supply not shown by means not shown and embedded within the flat ribbon 2 of wet pulpous fibrous material by suitable means such as disclosed in the patent mentioned, passes axially along through the helical member 3 which is supported as shown on a stationary pivot t, with enough looseness to follow freely small irregularities of direction of motion of the strand, but without freedom to rotate.

The member 3, as shown, is a suitable length of wire formed into a helix having five and a half effective turns. These turns are so formed as to envelop a tubular space whose diameter is largest in the first two turns from A to B, then smallest in the next two turns from B to C, and finally intermediate from C to D. The finished sheathed wire, emerging at D from the helix, has a definite predetermined overall diameter, say 01. The internal diameter of the helix from A to B is preferably about d, but may well have a value between 1.10d and d. The internal diameter from B to C is preferably about 095d, but may be from 0.8511 to 098d; while the internal diameter from C to D is preferably about 1.025d, but may be from 1.025d to 1.10d. In any event the A-B diameter is larger than cl, the BC diameter is smaller than 01, and the 0-D diameter is larger than d but preferably smaller than the AB diameter.

In a specific instance in which a 2d B and S gauge wire (diameter 0.0204 inch) was provided with a paper pulp sheath 0.008 inch thick, the overall diameter d of the sheathed Wire was 0.0365 inch, the AB diameter was about 0.046 inch, the BC diameter was about 0.034 inch, and the CD diameter was about 0.0375 inch. In this particular case the member 3 was chromium plated hard bronze wire with a diameter of about 0.081 inch, and the pitch of the helix was about 1.25 inches in the AB segment, about 1.00 inch in the BC segment and about 1.25 inches in the CD segment.

There does not appear to be any crucial relations among the diameter of the rod or wire of which the member 3 is composed, the pitch of its helix and the value d. However, optimum relations appear to be that the rod diameter of 3 should in general be not less than 11 and preferably from two to three times d, and that the length of a whole turn in the region from B to C should be from I lid to 15d and preferably about 25d to 30d. The exact number of turns in the helix is not crucial.

It is essential that the member 3 be mounted and supported in a manner to be held against rotation and yet to .be free to float on the strand advancing axially through it. .Also it appears to be preferable that the changes in diameter from the A.-B segment to the BC segment, and from this last to the CD segment be abrupt, the turns in each segment being substantially alike.

While theinvention is above detailed 'as applied specifically in the manufacture of 'pulp covered Wire, it is by no means so limited nor is it limited to the folding of a ribbon into cylindrical form. It is also useful, for example, wherever almost any kind of strand or coating on a strand is to be formed, compacted or polished, ortreated in any two or all three of these ways. 'Thuswherea wire sheathed in a served or braided 'coveringof textile strands or already providedwith ai'cylindrical sheath of paper pulp as described above, is to have its sheath externally coated with some liquid or viscous coating material such as molt-en wax, or a solution of cellulosic material, e.-g.cellulose acetate, or a liquid or pasty form of .superpolymeric material (e. g. the superpolyamids commercially known as Nylon, the superpolyisobutylenes commercialy known-asWistanex, certain superpolyethylenes, amylenes, isoamylenes,= etc), the device of the invention operates to form, compact and polish the coated sheathed strand, in a simple and'satisfactoryfashion.

, The embodiment of the invention herein rdisclosed is illustrative and may be variously :modified and departed from without departing from the spirit and scope of the inventionas pointed out in and limited only by the appended claims.

What is claimed is:

l. A device for treating-a strand drawn=axially therethrough comprising a rod-like member formed into a helix having a plurality of'turns and in which the internal diameter of-the first turns is greatest, that of the next turns -isleast, and that of the last turns is intermediate.

2. A device for treating a strand'drawn axially therethrough comprising a rod-like membier formed into a helix having aplurality of 'turns 4 and in which the internal diameter of the first turns is greater than the final diameter of itlie strand, that of the next turns is less thanthe final diameter of the strand,'and that of the -las't turns is greater than the final 'diame'terof'the strand.

3. A device for treating a stranddrawn axially therethrough comprising a rod-like member formed into a helix having-a pluralityof turns and in whichthe internal diameter of the ifirst turns is greater than the final diameter-of :the strand, that of the next turns is less than the final diameter of the strand, and that of the last turns is greater than the final diameter 'ofthe strand but less than that of the first turns.

4. A device for treating a strand drawn-axially therethrough comprising a rod-like 'merr'ibe'r formed into a helix having a plurality of turns in three consecutive groups, the internaldiameter of the turns in anygroupbeing-substantially uniform, the internal diameter of the first group .in three consecutivegroups, the internal ,diameter of the turns in any group beingsubstantially uniform, the internal diameter of the first group being greater than that of the strand emerging from the helix and greater than that of the second group, the diameter of the second group being less than that of the strand emerging from the helix, and the internal diameter of the third group being intermediate between those of the first and second groups.

*6. device for treating a strand drawn axially therethrough comprising a *rod like member formed into a helix having a plurality of turns in three consecutive groups, the internal diameter .of the turns in any group being substantially uniform, the internal diameter of the first group being greater than that of the strand emerging -from 'thehelix and greater than that of the second group, the diameter of the second group being less than that of the strand emerging from the helix, and the internal diameter of the third group being intermediate between those of the first and second groups and greater than that of the emerging strand.

v'7. A device for treating a strand to have -.an overall diameter 11 upon emergence from the .device, which device comprises-a rod-like member formed into a helix having a plurality of turns in three consecutive, groups the internal diameter of the first group being in the range of values whichinclu'des 1.1011 and 1.50d as extremes, the internal diameter of the second group being ,in

the range of values which includes 0.8511 and,

0L98d'as extremes, and th internal diameter of the third group being in the range of values which includes 1.025d and 1.10:1 as extremes. 7

8. A device for treating a strand drawn axially therethrough :to have anoverall diameter dupon emergence 'from the device, which device comprises arodlike member formed into a helix having a plurality of turns in three consecutive groups, the internal diameter of the first group being about 1:30d, the internal diameter of the second group being about 0.9501, and the internal 'diameterof the third group being about 1102521. -9. A device'for treating a strand drawn axially therethrough comprising a rod-like meniber formed into a helix having a plurality of turns and in which the internal diameter of the first turns is greatest, that of the next turns is least,

and that of the last turns is intermediate, "in combinationwith meansto support the helix to be held against rotation about its axis 'but "with freedom 'to float on the strand passing therethrough.

110. .A deviceiiortreating-a strand drawn-axially therethrough comprising a rod-like member rormedinto .a helix having a pluralityof turns and in which the internal diameter of itheifirs't turns is greater than the final diameter of the strand, that of the next turns is :less than the final diameter-of the :strand, and that of thelast turns is greater than the final diameter of the strand, :in combination with means tosu-pport the helix to be held against rotation about fits axis but with freedomtofioa't on the -strandpassing therethrough.

'11. -A device for treating a strand drawn axially therethrough comprising a rod-like memberformed into a helix having a pluralit-yof turns and in which the internal diameter of the first turns is greater than the final diameter of the strand, that of the 'next turns. is less than the finaldiameter of the strand, and that of the :last turns is greater than the final diameter :of the strand but less than that of the first turns, in combination with "means to support the helix to be held against rotation about its axis but with freedom to float on the strand passing therethrough.

12. A device for treating a strand drawn axially therethrough comprising a rod-like member formed into a helix having a plurality of turns in three consecutive groups, the internal diameter of the turns in any group being substantially uniform, the internal diameter of the first group being greater than that of the second group, and the internal diameter of the third group being intermediate between those of the first and second groups, in combination with means to support the helix to be held against rotation about its axis but with freedom to float on the strand passing therethrough.

13. A device for treating a strand drawn axially therethrough comprising a rod-like member formed into a helix having a plurality of turns in three consecutive groups, the internal diameter of the turns in any group being substantially uniform, the internal diameter of the first group being greater than that of the strand emerging from the helix and greater than that of the second group, the diameter of the second group being less than that of the strand emerging from the helix, and the internal diameter of the third group being intermediate between those of the first and second groups, in combination with means to support the helix to be held against rotation about its axis but with freedom to float on the strand passing therethrough.

14. A device for treating a strand drawn axially therethrough comprising a rod-like member formed into a helix having a plurality of turns in three consecutive groups, the internal diameter of, the turns in any group being substantially uniform, the internal diameter of the first group being greater than that of the strand emerging from the helix and greater than that of the second group, the diameter of the second group being less than that of the strand emerging from the helix, and the internal diameter of the third group being intermediate between those of the first and second groups and greater than that of the emerging strand, in combination with means to support the helix to be held against rotation about its axis but with freedom to float on the strand passing therethrough.

15. A device for treating a strand drawn axially therethrough to have an overall diameter d upon emergence from the device, which device comprises a rod-like member formed into a helix having a plurality of turns in three consecutive groups, the internal diameter of the first group being in the range of values which includes 1.1011 and 1.50d as extremes, the internal diameter of the second group being in the range of values which includes 0.85d and 0.9812 as extremes, and the internal diameter of the third group being in the range of values which includes 1.02511 and 1.1011 as extremes, in combination with means to support the helix to be held against rotation about its axis but with freedom to float on the strand passing therethrough.

16. A device for treating a strand drawn axially therethrough to have an overall diameter d upon emergence from the device, which device comprises a rod-like member formed into a helix having a plurality of turns in three consecutive groups, the internal diameter of the first group being about 1.30d, the internal diameter of the second group being about 0.95d, and the internal diameter of the third group being about 1.025d, in combination with means to support the helix to be held against rotation about its axis but with freedom to float on the strand passing therethrough.

JOHN N. SELVIG. 

